猫鼬会自动减少数字类型的字段

Question

我目前在我的项目中使用过猫鼬，这是我的架构：

const mongoose = require('mongoose');
const classSchema = mongoose.Schema({
  _id: mongoose.Schema.Types.ObjectId,
  consultant: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'Consultant',
    required: true,
  },
  faculty: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'Faculty',
    required: true,
  },
  startYear: {
    type: String,
    required: true,
  },
  currentSchoolYear: {
    type: String,
    required: true,
  },
  currentSemester: {
    type: String,
    required: true,
  },
  classname: {
    type: String,
    required: true,
    unique: true,
  },
  classSize: {
    type: Number,
    required: true,
  },
  warnedLength: {
    type: Number,
    required: true,
  },
});

const Class = mongoose.model('Class', classSchema);

module.exports = Class;

如您所见，我有2个属性分别是classSize和warnedLength是Number。现在，我想创建一个函数，当我单击客户端上的按钮时，classSize和warnedLength的值将自动减小1。无论如何，有这样做吗，非常感谢您的帮助我出去，对我来说意义重大，祝你有美好的一天